JP2010536352A - Method for producing distilled olive juice extract - Google Patents

Abstract

  The present invention presents a novel process for the production of olive juice extract, which is all natural, rich in hydroxytyrosol and has no bitter taste, and its distillate. The novel juice extract distillate and compositions containing the novel olive juice extract distillate are also part of this invention.

Description

Detailed Description of the Invention

[Field of the Invention]
The present invention relates to distilled olive juice extracts and methods for producing these extracts. Since olive juice extract has strong antioxidant activity, it can be used as a nutritional supplement. Nutritional compositions containing these novel extracts are also part of this invention.

[Background of the invention]
The medicinal properties of olive oil and olive extract are widely recognized. To produce olive oil, olive fruit is ground into a paste. Pressure is applied to the paste to separate the oil from the crushed fruit. In addition to providing olive oil, pressing also releases the water content of olive fruit containing many water-soluble phytochemicals. This water is known by several names including “vegetable water, olive juice and olive wastewater”. Interestingly, while olive juice and its disposal are problematic for olive oil producers, this olive juice can be a desirable rich source of phenolic compounds that can have advantageous nutritional properties.

  In the past, methods of concentrating nutritive olive juice have involved time-consuming culture, filtration and / or centrifugation and / or spray drying steps. Another problem is the usefulness of dried or liquid olive juice in foods or dietary supplements due to the smell, bitterness and turbidity of olive juice and the low content of hydroxytyrosol, one of the active polyphenols Is limited.

  It is therefore desirable to develop a better method for producing an efficient and cost-effective olive juice extract that is all natural, rich in hydroxytyrosol, and has no bitter taste. Let's go.

[Description of the Invention]
The present invention presents a novel process for producing an olive juice extract distillate that is all natural, rich in hydroxytyrosol, and free of bitterness. The novel juice extract distillate and compositions containing the novel olive juice extract distillate are also part of this invention.

  A typical olive is about 50% water, 22% oil, 19% carbohydrate, 6% cellulose, 2% protein, and (in combination) 0.2% oleopane and hydroxytyrosol. Containing. It should be understood that the exact composition of the fruit (and subsequent extract) will vary depending on the olive variety used, the time of harvest and even the growth conditions.

  Contrary to literature reports (see, for example, Briante et al., 2002, J. Biotechn. 93: 109-119, and Soler-Rivas et al. 2000, J Sci Food Agric 80: 1013-1023) It was found that the unknown compound that gives to olive juice is neither hydroxytyrosol nor oleuropein. While not wishing to be bound by theory, they may contain labile phenol ester groups. Regardless of the identity of the bitter compounds, they are very sensitive to bases and are not stable at higher pH.

As used throughout this specification and the claims, the following definitions apply:
“HT” means hydroxytyrosol.
“Olive juice”, “olive wastewater” and “vegetable water” are all terms used interchangeably. They refer to the aqueous phase that is produced during olive oil production. It is a slurry of complex mixtures of carbohydrates with compounds of interest such as HT and oleuropein (contains bound HT, which can then decompose to yield HT).

Therefore, one embodiment of the present invention provides
a) obtaining a hydroxytyrosol-enriched olive juice concentrate that is clear, reduced in solids, reduced in triglycerides, and reduced in fatty acids;
b) A process for producing olive juice rich in hydroxytyrosol comprising distilling the hydroxytyrosol extract from step a) to form an olive juice distillate.

Another aspect of the present invention is:
a) obtaining an olive juice extract in which the amount of solids, triglycerides and fatty acids is substantially reduced compared to untreated olive juice;
b) extracting the olive juice extract with a water-immiscible solvent to obtain a hydroxytyrosol extract;
c) Distilling the hydroxytyrosol extract to form an olive juice distillate, which is a method for producing an olive juice distillate rich in hydroxytyrosol.

  If triglycerides, free fatty acids or other esters (such as olive oil, oleic acid and oleic acid ethyl ester) are present in olive juice, it can be reduced or completely removed before distilling the juice to prevent contamination of the distilled HT Must be removed. Fatty acids and esters are not soluble in HT, but fatty acids and simple esters (such as oleic acid and ethyl oleate) are distilled with HT, thus forming a turbid or two-phase distillate.

[Distillate formation with reduced triglycerides, fatty acids and ethyl oleate]
There are two main typically commercially available forms of olive juice that can be used in the present process of the present invention. The first is fresh olive juice. This can simply be obtained untreated from the creator (typically the olive oil producer) or can be subjected to procedures such as centrifugation or filtration to remove solids and triglycerides. After rehydration, a second form that can be used in the present invention is a spray dried or lyophilized form stabilized with citric acid. Any source can be distilled after treatment as described below. Typically, the starting juice may contain solids, fat (oil) and / or fiber in it, or after pretreatment such as centrifugation or ultrafiltration, the solids and triglycerides or fatty acids. Not included. Also suitable are olive juices purchased in concentrated form or concentrated prior to use by standard techniques known in the art.

  If necessary, it is possible to remove some of the fibers and / or non-volatile materials by ethanol precipitation as described in the co-pending patent application [Attorney Docket No. 26254WO] and outlined herein It is.

  Typically, raw olive juice contains a large amount of fine fibers. These tend to clog membrane filters and require enormous maintenance, making them difficult to filter. Fibers, residual oils and lipids and / or other solids present in olive juice are capable of agglomeration, and a) (by volume) about 40 to 40% of olive juice or partially concentrated olive juice. It can be easily reduced by adding solvent in an amount equal to 400% to form two phases and b) separating the two phases.

  The solvent that can be used in the process can be any water-miscible or nearly miscible solvent or solvent mixture, such as n-butanol. Especially when the final product is used in food or as part of a pharmaceutical or nutritional product, alcohols, especially C1-C4 (or mixtures thereof) are preferred, and ethanol is particularly preferred. Other solvents that can be used also include acetonitrile and acetone.

  The amount of solvent is not particularly critical and depends on the amount of water in the mixture. Usually, the solvent is required in an amount at least equal to the amount of water present. Therefore, for example, when ethanol is a solvent, about 600 ml of EtOH is required for 500 ml of water. However, this tends to be a broad range: about 40-400% by weight solvent compared to the amount of water, preferably 100-240% compared to the amount of water, more preferably about 160-220% solvent. There is. An important criterion is that enough solvent is added so that two distinct phases are formed.

  The temperature of this step is not particularly critical and may range from 0 ° C. to about 80 ° C., or any temperature below the boiling point of the mixture. Conveniently, the temperature is about 20 ° C. to 60 ° C., most conveniently room temperature or about 25 ° C.

  At this point, there are two phases and any convenient means can be used to separate the two phases. The separation method depends on the actual composition of the material. For certain batches, filters and / or centrifuges can now be easily used. Other batches can be easily processed by simple decantation or normal phase separation.

  If desired, the solvent can be recovered for reuse to make the process more economical. Evaporation is generally the simplest way to recover the solvent.

  The resulting product is an olive juice extract with reduced solids, triglycerides, fatty acids (eg, oleic acid) and fatty acid ethyl esters (eg, oleic acid ethyl ester), which is the starting point for the next step of the present invention. Can be used as a substance. Decrease means that the amount of solids, triglycerides, fatty acids and oleates remaining in the extract is substantially reduced and almost undetectable. If necessary, triglycerides, fatty acids and ethyl oleate can be further reduced by extraction with n-hexane or by centrifugation and / or decantation. In order to obtain optimal results, it is preferred that the amount of these components be as low as possible (less than about 1%). In a particularly preferred embodiment, the olive juice extract is free of solids, free of triglycerides, free of fatty acids, and free of fatty acid ethyl esters.

[HT Extraction]
According to the present invention, by using a water-immiscible solvent such as ethyl acetate, methyl acetate, butyl acetate and THF, clear, solids, triglycerides, fatty acids and ethyl oleate are reduced as obtained from the above step. It was found that hydroxytyrosol can be extracted from the obtained olive juice extract. For most applications, including those where the final product is intended to be used as a nutritional product or drug, ethyl acetate, particularly food grade ethyl acetate, is preferred.

  To increase the content of hydroxytyrosol in the extract, it is preferred to extract at a higher pH (such as 8-9), but any pH in the range of about 3-11 can be used. Hydrolysis at a pH higher than about 9 also forms free oleic acid, which can be extracted with n-hexane at a slightly acidic pH (less than about 6) if necessary.

  Due to the relatively low partition coefficient (EtOAc / water is about 1), it may be necessary to repeat the extraction several times or to perform the extraction on a multi-stage extraction column for optimal results. Can do. Although such an extraction factor of HT is not affected by pH (at pH 4-8), at lower pH, a significant amount of unknown compounds are also extracted, thereby the purity of HT in the extract Extraction is more efficient at a pH of about 7 or higher.

  The extract so obtained from the extraction step constitutes yet another aspect of the present invention. The extract is clear and has a reduced amount of solids, a reduced amount of triglycerides and a reduced amount of fatty acids compared to the starting olive juice. Preferably, “amount reduced” is very low, ie present in an amount that is less than 10% of the amount present in the starting fruit juice, and more preferably is hardly detected.

  In another step, instead of extracting HT from an olive juice extract that is clear and reduced in solids, triglycerides, fatty acid oleic acid ethyl ester, it can be concentrated using an adsorption process. For example, instead of extracting hydroxytyrosol with a solvent in a process as described in EP 2172429, WO 02/064537, the hydroxytyrosol is enriched by adsorption on a resin. can do. In this process, a chromatographic treatment using a neutral resin, preferably AMBERLYST XAD or a similar type of resin, is preferred.

[Distillation of HT extract]
In any of the above processes, the resulting HT-enriched extract can now be distilled using conventional or preferred short path distillation equipment. If olive juice has a lower HT concentration (ie, less than about 10%), HT is distilled despite the reported pure HT distillation (Baralda et al. 1983 Liebigs Ann. Chem. 684-686). Distillate is not possible because it cannot be done or because HT decomposes.

  In accordance with the present invention, surprisingly, after extraction, the enriched extract containing at least about 30% HT is distilled to produce a higher concentration distillate in high yield (greater than about 60%). It has been found that it is possible to obtain.

  In a preferred embodiment, the distillation is performed at a vacuum of less than about 2 mbar. The resulting distillate forms yet another aspect of the present invention, which is a nearly colorless and very viscous liquid containing about 50-85% HT and 8-15% tyrosol. To do.

  If desired, tyrosol can be almost completely removed by subjecting the distillate to a second fractional distillation. Accordingly, another aspect of the present invention is to redistill a previously obtained distillate to produce a redistillate having a hydroxytyrosol to tyrosol ratio of 10: 1 to> 50: 1. is there.

  The distillate of the present invention (ie, the distillate produced after the first distillation and the distillate produced after the second distillation) can be used in combination with conventional feeds, foods or beverages for humans. Or it may be a component of an animal nutritional item. Furthermore, the distillate may be prepared into pharmaceutical products such as tablets, capsules, liquids using conventional methods. Alternatively, they can be used as part of a cosmetic composition.

  The invention is further illustrated in the following non-limiting examples.

[Example]
[Example 1]
[Starting material]
Unless stated otherwise, all stated percentages refer to weight percent.

The starting material was HIDROX 6% (CreAgri, Haywood, CA). (Lot 6022406002. This is lyophilized olive juice stabilized with citric acid. Its content is as follows.% By weight):
Carbohydrate: About 60%
Lipid (olive oil): about 15%
Fiber: About 10%
Hydroxytyrosol: 2.1%
Water: about 2%
appearance:
Solubility in water: cloudy fine suspension Flavor: bitter Color: beige brown powder

[Example 2]
To a reaction flask in a nitrogen atmosphere was added 100 g of HIDROX (6% polyphenol) from CreAgri (Example 1) and 80 ml of water. The mixture was warmed to 80 ° C. and adjusted to pH 9.0, followed by a continuous addition of 38 ml of 10 mol / l sodium hydroxide to maintain the pH, at 80 ° C., pH 9. Stir at 0 for 30 minutes. The suspension was cooled to 60 ° C. The content of hydroxytyrosol was increased to about 130% by base treatment.

  By adding 200 g of ethanol, solids and precipitating material precipitated at 60 ° C. The mixture was cooled and stirred at ambient conditions for 30 minutes and filtered through a Buchner funnel. The filter cake was washed with 50 g of ethanol 70% / water 30%. The filtrate was adjusted to pH 5 with about 5 ml of 10 mol / l hydrochloric acid and evaporated with a rotor vapor (20 mbar, 60 ° C.) to recover the ethanol, giving 33.5 g of a non-volatile residue. Content [wt%]: 7.4% hydroxytyrosol, 0.8% tyrosol. Yield: 119% of the initial hydroxytyrosol.

  The residue (33.5 g) was dissolved in 32 ml of water. Traces of fatty acids and oils were extracted with 100 ml n-hexane. The aqueous phase was adjusted to pH 8.0 with about 4 ml of 10 mol / l sodium hydroxide and extracted with 5 × 100 ml of ethyl acetate. The organic phase was washed successively with 10 ml water. The ethyl acetate solutions were combined and evaporated to give 3.29 g of hydroxytyrosol. Content [wt%]: 66.0% hydroxytyrosol, 8.3% tyrosol. Yield: 103% of the initial hydroxytyrosol.

  2.97 g of the extracted hydroxytyrosol was distilled with a short path distillation apparatus of 0.02 to 0.2 mbar to obtain 2.38 g of hydroxytyrosol. Content [wt%]: 80.1% hydroxytyrosol, 9.7% tyrosol. Yield: 101% of the initial hydroxytyrosol.

[Example 3]
Short-path distillation of 19.7 g of hydroxytyrosol (content: 70% hydroxytyrosol, 11% tyrosol) was fractionally distilled through a column in vacuum (0.02-0.2 mbar), 86% With a content of hydroxytyrosol, 2.6% tyrosol, 9.6 g of hydroxytyrosol was obtained.

[Example 4]
A concentrated olive juice sample from which the fiber was removed was obtained (content = 0.89% hydroxytyrosol). 243 g was further concentrated in vacuo to 190 g (containing about 50% non-volatile material). In a reaction flask under a nitrogen atmosphere, the mixture was warmed to 80 ° C. and adjusted to pH 8.0, followed by continuous addition of 32 ml total of 10 mol / l sodium hydroxide to maintain the pH. , And stirred at 80 ° C. and pH 8.0 for 30 minutes.

  To the dark mixture was added 280 g of ethanol and a precipitate formed. The mixture was cooled and stirred at ambient conditions for 1 hour. The supernatant of the solution was decanted from the precipitate and evaporated with a rotor vapor to recover the ethanol. The nonvolatile residue was 78 g. Content [wt%]: 2.6% hydroxytyrosol, 0.6% tyrosol. Yield: 93% of the initial hydroxytyrosol.

  The residue (78g) was dissolved in 77ml water and extracted with 5x100ml ethyl acetate. The organic phase was washed successively with 10 ml water. The ethyl acetate solutions were combined and evaporated to give 4.0 g of hydroxytyrosol. Content [wt%]: 40.3% hydroxytyrosol, 9.4% tyrosol. Yield: 74% of the initial hydroxytyrosol.

  3.6 g of the extracted hydroxytyrosol was distilled with a short path distillation apparatus of 0.02 to 0.2 mbar to obtain 3.0 g of hydroxytyrosol. Content [wt%]: 41% hydroxytyrosol, 14.6% tyrosol. Yield: 63% of the initial hydroxytyrosol.

Claims (17)

A method for producing an olive juice distillate rich in hydroxytyrosol,
a) obtaining a hydroxytyrosol-enriched olive juice concentrate that is clear, reduced in solids, reduced in triglycerides, and reduced in fatty acids;
b) distilling the hydroxytyrosol extract from step a) to form an olive juice distillate. Compared to fresh olive juice, olive juice extract containing reduced amounts of solids, carbohydrates, triglycerides, fatty acids is extracted with water-immiscible solvent to produce hydroxytyrosol-enriched olive juice concentrate A process for producing an olive juice distillate rich in hydroxytyrosol according to claim 1, wherein the olive juice concentrate of step a) is formed by a process comprising obtaining.   The method of claim 2, wherein the extracting step further comprises adjusting the pH to about 3 to about 11.   4. The method of claim 3, wherein the pH is adjusted to about 5 to about 10.   The method of claim 4, wherein the pH is adjusted to about 7 to about 9.   The method of claim 2, wherein the water-immiscible solvent is selected from the group consisting of ethyl acetate, methyl acetate, butyl acetate, THF, and mixtures thereof.   The process according to claim 6, wherein the solvent is ethyl acetate.   8. The method of claim 7, further comprising removing at least a portion of ethyl acetate and recovering ethyl acetate prior to step b).   The process according to claim 1, wherein the hydroxytyrosol-enriched olive juice concentrate is produced by adsorbing olive juice on a resin.   The method according to claim 9, wherein the resin is an AMBERLYST XAD type neutral resin. c) re-distilling the distillate from step b) to produce a redistillate having a hydroxytyrosol to tyrosol ratio of about 10: 1 to> 50: 1. The method according to any one of 10 above.   The process according to claim 1, wherein the olive juice extract of step a) is produced by a process comprising hydrolysis of olive juice at pH 7-9 and temperature 60-90 ° C.   The olive juice extract produced by the method according to any one of claims 1 to 10, which is transparent and contains a reduced amount of solids, carbohydrates, triglycerides, fatty acids compared to fresh olive juice. object.   The olive juice distillate or redistillate manufactured by the method as described in any one of Claims 1-12.   A nutritional composition comprising the composition according to claim 13 or 14.   A feed composition comprising the composition according to claim 13 or 14.   A cosmetic composition comprising the composition according to claim 13 or 14.